COVER-SLIPS AND SECTfONS. 277 



and represent the result of disintegration going on in 

 these cells. 



Beyond this area we come upon a dense, deeply stained 

 zone, consisting of closely packed pus-cells ; of granular 

 detritus resulting from destructive processes acting upon 

 these cells ; and of the normal cellular and connective- 

 tissue elements of the part. Here and there through 

 this zone will be seen localized areas of beginning death 

 of the tissues. This zone gradually fades away into 

 the healthy surrounding tissues. It constitutes the so- 

 called " abscess- wall." 



Such is the picture presented by the miliary abscess 

 when produced experimentally in the rabbit, and it cor- 

 responds from beginning to end with the pathological 

 changes which accompany the formation of larger ab- 

 scesses in the tissues of human beings. 



From these small abscesses in the tissues of the 

 rabbit staphylococcus pyogenes aureus may again be 

 obtained in pure culture, and will present identically 

 the same characteristics that were possessed by the cult- 

 ure with which the animal was inoculated. 



A characteristic of all staphylococcus abscesses, small 

 as well as large, is centralized death of tissue ; even in 

 those of microscopic dimensions this area of necrosis 

 is always discernible by appropriate methods of exami- 

 nation. It represents the very starting-point of the 

 destructive process, and is referable to the action upon 

 the tissues of poisons elaborated by living bacteria that 

 have gained access to them. 



As a result of the studies of van de Velde, Krauss, 

 von Lingelsheim, Xeisser and AVechsberg, and others, 

 our knowledge of the poison that causes the destruction 

 — staphyloto?iin; as it is called — has been greatly ex- 



